That was then: The Quinnipiac Poll assumes Democratic turnout this year will be greater than in 2008, when Obama filled Denver’s Invesco Field. Photo: AP

Yesterday’s Quinnipiac Poll results were great news for President Obama: The Q-poll has him ahead by substantial margins in three battleground states — up 9 points in Florida, 10 in Ohio and 11 in Pennsylvania.

Take a closer look: These numbers seem less like a scientific effort to measure how the campaign is going, and more like a drive to push it in that direction.

Simply put, the Quinnipiac surveys oversample Democrats; they only make sense if we believe that President Obama’s supporters are going to turn out in even greater numbers (relative to Republicans) than they did in 2008.

Questions about the partisan makeup of poll samples have been rampant this election season, and Quinnipiac (which recently partnered up with CBS and The New York Times for polling) is at one extreme of that debate.

The 2008 election was a banner year for Obama and Democrats in general. The top of the ticket was a historic candidate (now our nation’s first black president); America had war and Bush fatigue, and the financial meltdown created an anti-Republican wave.

Plus, Obama’s opponent, despite a great biography, was a poor candidate — a foreign-affairs and military expert running when the economy was the issue. John McCain’s campaign also had far less cash to spend.

All these factors helped yield to a strong Democratic advantage at the voting booth — where more voters identified themselves as Democrats than Republicans by a remarkable 7 points, 39 percent to 32 percent.

This was the best advantage for Democrats in over a generation; in polling shorthand, we refer to it as D +7.

For comparison, the 2004 split in party ID was perfectly even at 38 percent apiece (the GOP’s best showing in any recent presidential contest), and the average split in modern elections is D +3.6.

But Obama’s advantages are clearly less strong this year. He’s given us 8-plus percent unemployment for three years, economic growth below 2 percent and 23 million unemployed — and now the American flag is being burned across the Muslim world. Plus, Mitt Romney’s ground game far exceeds McCain’s 2008 effort.

But the Q-poll is having none of it. Like some other polling outfits, it is consistently and systematically insisting that Election Day turnout will favor Democrats as much or more than Obama’s 2008 best-in-a-generation advantage.

In the Q-polls released yesterday, the spread between Democrats and Republicans each exceeded Obama’s 2008 advantage.

In Florida, the 2008 actual result was D +3; yesterday’s Q-poll had it at D +9. In Ohio, it was D +8 in 2008, D +9 in the Q-poll. And Quinnipiac gave us D +11 in Pennsylvania, versus a 2008 result of D +7.

Mind you, each of these states has seen dramatic changes in party preferences since 2008 — electing Republican governors, flipping the state legislatures to GOP control, etc.

Quinnipiac and others have given us polling that reflects a Democratic edge exceeding 2008 all year — including in last week’s Q-polls on Colorado, Virginia and Wisconsin.

Doug Schwartz, the director of Quinnipiac Polling, recently addressed these criticisms, citing the change from 2004 to 2008 to justify his sampling: “A good example for why pollsters shouldn’t weight by party ID is if you look at the 2008 presidential election and compare it to the 2004 presidential election, there was a 7-point change in the party-ID gap.”

Um, so why is Schwarz assuming that the trend from 2004 to 2008 will continue in 2012?

Again, we have a president mired in a weak economy — with the economy remaining voters’ top issue (no survey even shows a close second). And Obama’s 2008 voting coalition is less enthusiastic in 2012, especially Hispanics and the youth vote.

But Quinnipiac uses 2008 as the norm — and then adds in even more Democrats, because, says Schwartz, there are “more people who want to identify with the Democratic Party right now than the Republican Party.”

Yes, more people identify with Democrats — that’s why national polls should reflect a sample that’s D +2 or D +3, and state polls should reflect a sample between the 2004 and 2008 electorates — not the unusually and likely unrealistically large Democratic advantage that Quinnipiac is awarding President Obama.

Kevin Patrick blogs about the presidential campaign as “Keith Backer” at battlegroundwatch.com.